1. Field of the Invention
This invention relates to a satellite information autonomous distribution satellite, satellite information collection system and satellite terrestrial test system, and more particularly to a satellite information autonomous distribution satellite, satellite information collection system and satellite terrestrial test system capable of collecting satellite attribute information even after something goes wrong or hinders the satellite, or even in terrestrial testing prior to launching.
2. Description of the Related Art
Communication between various satellites launched into orbit and terrestrial stations is usually carried out using electromagnetic waves. For example, it is possible to acquire various information (status information or attribute information, hereafter referred to as attribute information) for the satellite using telemetry command lines from a satellite. As a result, it is possible to be aware of the state of the satellite at this time, and it is possible to monitor, analyze and study etc. the state of the satellite in orbit.
However, in the event that something goes wrong with the satellite such as, for example, a problem such as it no longer being possible to use a transponder, etc., it is often not possible to acquire attribute information for the satellite using the directory command line. Because of this, with regards to satellite trouble and the state and cause of a malfunction, it is only possible to go as far as deducing the state and cause of this based on the conditions etc. up to the time of the trouble or malfunction.
Further, means for retrieving target satellites that are the subject of abandonment or recovery have been proposed (refer to Japanese Patent Laid-open Publication No. 2004-098959). If the malfunctioning satellite or satellite waste etc. is recovered using a separately launched working satellite, it is possible to directly investigate the cause of problems or malfunctioning in the malfunctioning satellite etc.
It is not possible to acquire sufficient attribute information from before the occurrence of the problem of malfunction of the satellite because the communication speed of the directory command line is low. In particular, because it is not possible to acquire sufficient attribute information for the conditions etc. up to the occurrence of the problem or malfunction, it is not possible to deduce the cause etc. of the malfunction of the satellite etc. in a fixed proportion of cases. Further, there is little (or no) attribute information regarding specific problems for which it was originally thought that recovery was possible, so that recovery is not possible, or it may not be possible to cause the satellite to operate due to it being in an involuntary state (light load mode (LLM; Low Load Mode) states).
Further, after a satellite has been subjected to trouble or has malfunctioned, communication means for a satellite for which trouble has occurred so that transponders cannot be used or for malfunctioning satellites are cut, and attribute information for the satellite cannot be acquired using a directory command line. It is therefore not possible to acquire attribute information thereafter, and it is therefore only possible to extrapolate the cause etc. of the problem etc. with the satellite, or it is not even possible to extrapolate the cause. In this event, even if it is possible to extrapolate the cause etc. to a certain degree of accuracy from past experience, it is only ever possible to assume the specific cause.
On the other hand, if the malfunctioning satellite is recovered, it is possible to reliably know the cause of the satellite malfunction but this tends to be prohibitively expensive. This is therefore not appropriate for all satellites. Further, it is not possible to recover satellites that are still operating in orbit even though they may be somewhat damaged.
In addition to the above, various tests are carried out on a satellite terrestrially prior to launch of the satellite. In this event, as it is not possible to use a telemetry command line, a cable, for example, is connected between a satellite arranged in a vacuum chamber and external test apparatus, and various test data is acquired. Unfortunately, with this method it is necessary to annoyingly carry out the cabling every time a test takes place. Further, the load here is substantial because it is necessary to provide a different cable connection section every satellite at test apparatus such as the vacuum chamber.